In the lead-up to Halloween, Experian Hitwise data shows searches for variations of “costume” and “costumes” are up about 3% over 2010 (share of search 20 weeks before Halloween through five weeks before Halloween in 2011 vs. 2010). Moreover, as PriceGrabber reports that 73% of American consumers will spend money on a new costume and 50% will purchase Halloween-related décor, the National Retail Federation is anticipating an 18% increase in Halloween-related spending this year over last . This is the perfect time for retailers and content providers to capitalize on web-users’ desire to spend, to save and to get great ideas for Halloween 2011.

Examining the list of top variants by type of costume, it’s clear that Hollywood and pop culture are driving much of the demand for costumes this year. Movies like Disney’s “Tangled” http://adisney.go.com/disneypictures/tangled/ driving growth in searches for “Rapunzel costume” and the upcoming Batman film pushing increasing interest in “Catwoman costume”. On the male-focused side, we’re seeing an escalation in searches for Captain America, also Batman costumes and Mortal Kombat.

*Note: Chart is sorted by greatest percentage point increase.

Though Lady Gaga-themed get-ups are still very much in demand, Nicki Minaj and Katy Perry fans will be out in force this Halloween, with Hitwise data noting a strong rise in searches for costumes related to both stars.

Halloween is mostly about candy and good times, but it’s very heartening to know that Unicef still sees an increase in interest and searches for variations of “Unicef” each year in October, as children prepare to join Unicef’s trick-or-treat campaign.

Serena Williams’ appointment as a Goodwill Ambassador for Unicef caused an early bump in “Unicef” searches and given the dire needs of people in the Horn of Africa, one can only hope that this year’s trick-or-treat campaign successfully converts searches into donations.

Thanks to Margot Bonner, Analyst on the Custom Data & Insights team for helping with today’s analysis.